This invention is an improvement to the adhesive fastener used for file folders of the type shown in U.S. Pat. No. 5,169,254, dated Dec. 8, 1992.
This type of fastener is typically mounted in a conventional file folder on a prong fastener along the top edge of the file folder panel. The adhesive fastener pieces are hole punched and fit on the prong fasteners of the file folder. They are small rectangular pieces each of which has a contact adhesive on its undersurface which engages the top edge of a paper to be secured in the file to hold it in place. The adhesive on each adhesive fastener is covered by a release paper which is removed when the fastener is to engage a paper sheet inserted in the file. All of the fasteners are flexible pieces. The adhesive fasteners are successively connected to paper sheets as they are inserted in the folder starting with the lowermost fastener. All of the unconnected adhesive fasteners are bent upwardly to provide an opening under the lowermost unconnected adhesive fastener. The paper sheet is inserted in this opening and aligned in position on the panel with previously inserted papers.
Removal of the adhesive covering on the fastener immediately above this newly inserted paper sheet will permit the adhesive on that fastener to adhere to that paper sheet when the upwardly bent fasteners are released and a slight rub or press applies a downward pressure to adhere the fastener to the paper sheet.
This unique type of file folder fastener piece allows papers to be inserted more quickly, and eliminates the two-hole punch operation. The adhesive fasteners are constructed of clear, flexible, plastic material, and the adhesive is a reusable type, so that the pages may be quickly removed, copied, and replaced, without disturbing the other pages in the file. The fastener provides greater holding power than an ordinary paper that is two-hole punched. Tapes will not tear out of the file.
During the course of development of the adhesive fastener for file folders, limitations in materials, adhesives, and arrangement of the component parts were encountered. The adhesive fastener configuration of this application is an outcome of such development efforts.
The specific type of fastener material, for example, is of specific interest with respect to how fastened papers of the file fold back over the file during use. The type of adhesive and the substrate are important with respect to consistent holding power of the fastener, and also ability to separate the adhesive of the fastener from an inserted paper sheet. The width of the contact adhesive and its positioning affect both movability of the fastener attached paper sheets and also affect the hinge action provided by the fastener.
The lower free section with this configuration also provides a lifting section which is sufficiently wide to be grasped between the fingers of the user to separate the adhesive fastener from the paper to which it is attached.
Although a strong bond is provided by the adhesive to the paper, the paper can be quickly removed by pulling up the fastener from the paper. This combination of strength and releasability is not achieved with the holding power of ordinary contact adhesives. Their bond is either too strong, so that one cannot remove the bonded pieces, or, as in the case of the adhesive notes, the bond has no holding power. It has been found that in the setting of a file folder, a relatively small mid-range of adhesive strengths of sufficient holding power provided in the transverse direction parallel to the attached papers, is sufficient. Yet, the lower holding power or tack, than strong bonding adhesives, will permit the separation of the fastener from the paper, when the fastener is pulled upwardly away from the surface of the paper. The strength of the adhesive in the selected range is also great enough to resist papers being pulled away from the fastener when papers are folded back over the top of the file folder.
Consequently, the adhesive fastener of this invention provides the capability to quickly place a paper in a file, to hold it more securely than ordinary two-hole punched papers, and yet permits the paper to also be quickly removed, if desired, and subsequently replaced in the file folder.
Additionally, the contact adhesive on the file fastener provides a flexible hinge connection for a paper, so that it can be readily folded back over the top of the folder without the spring back problem encountered with ordinary two-hole punched paper fastening devices. This is accomplished by spacing the contact adhesive a distance from the prong fasteners so that a hinge area is provided.
The filed paper positioned anywhere in the file folder is readily separated from the fastener without requiring dismantling of the other papers in the file. This is not possible with conventional prong fastener mounted papers in a file folder. The fastener is easily pulled free of the paper to which it is attached, and the paper simply removed. If desired to reinsert the paper subsequently, the paper is merely inserted under the fastener as previously. To do this, a marking paper is placed underneath the paper to be removed from the file, so that the adhesive will then engage that paper during the time that the removed paper is absent from the file. To replace, the removed paper is merely placed in position underneath the marking or holding paper, and the making paper is removed, leaving the contact adhesive of the fastener now free to reengage the top surface of the removed fastener, as before.
The removal of a paper is a very simple operation. The fastener is simply pulled free. The positioning of the contact adhesive remotely from the lower edge of the fastener. The lower free area permits the user to grasp it and pull the fastener upwardly, this construction feature permits handy and quick disengagement of the fastener.
It has also been found that disengagement of the fastener can be substantially speeded, without reducing the holding power of the fastener. Surprisingly, it has been found that a reduction of approximately 50 percent in the width of the adhesive will allow quicker disengagement, without adversely effecting the holding power of the fastener. Apparently, because the larger force is ordinarily required up along a line parallel to the paper surface of the adhesive, and when the upward force is exerted, or when papers are folded over, the holding force required is substantially less, although transverse to the bonded surfaces, therefore a reduced adhesive width is possible. Also the reduction in peeling time (removal) is substantial and there is a substantial reduction in cost, since tape is expensive.
Use of two sided adhesive tape also is a major advance in providing a more reliable fastener, and one that does not require complex manufacturing techniques. Attempted production of fasteners with direct application of adhesive to the fastener surface presented quality control problems, as well as problems. economical production techniques. Purchasable commercial tapes, having high tack holding power on one side, providing a permanent bond to the fastener, and a lower tack releasable adhesive within the limits desired, were found and provided reliability, as well as simplified manufacturing techniques. However, finding a commercial tape having the quality control and reliability within the limits needed was difficult but was eventually found.
These and other features and advantages of this adhesive fastener invention will become apparent to those skilled in the art when taken with respect to the following detailed description of the preferred device.